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If the geology anon(s) is around, I've been researching the topic of Sakuran's volcanoes and hot springs. I've only placed these generally by feel after reading through a number of articles, so if anyone is more well-versed on these matters I'd appreciate your input.
The whole volcanically active area is, from what I've calculated, ~500-600km (scale pending). From that: the dark orange area, measuring 75kmx50km at its longestxwidest, is the main volcanically active area and the centre of the shield volcano Mt. Achuachu; the moderately orange area is semi-active, where lave does flow underneath, giving rise to cinder cones (marked in small red circles), but no shield-related fissures occur; and the light orange/yellow area that is comprised of old lava flows when the volcano was more active which are now fully covered in soil.
Of the 5 noted cinder cones, the two westernmost went extinct before 35p even arrived in this land, the centre one went extinct a couple of centuries ago and the two easternmost ones are currently active, having each exploded twice in the last century.
Regarding geology: Due to the main volcano being a shield type, silica concentration in the rocks of the area is low. Generally, the volcano would release volcanic rocks of classifications, following the TAS diagram, mostly B, but also O1, S1, S2 (Mugearite), Pc, U1 (Basanite) and F (Nepheline, Nosean etc) .
Exceptions to this appear in the area where the 5 cinder cones have risen (roughly the blue circle area), where lava was enriched with slightly higher amounts of silica, forming volcanic rocks of classiciations O2, S3, U2 and F (Analcime, Lazurite etc).
The large circled areas mark the general locations of hot springs, while the long purple lines the underground water systems that flow through the land.
To the north, within the green circle, bicarbonate hot springs can be found. Their water has a green-blue colour due to the species of bacteria residing in them, while cooler ones develop thin green films over them and eventually vegetation.
To the west, the orange contains an area of mostly iron-rich hot springs, with some acid sulfate ones spread in-between. These are the most numerous hot springs in the country. Iron-rich hot springs are easy to differentiate, as they all have colouration varying from red to dark red to brown, due to the iron oxide produced by the bacteria that make their home there. Most of these Iron-rich hotsprings are harmful to both humans and plants, specifically tubes and roots, and especially potatoes, causing scab disease and soft rot disease. However, rare iron-rich hot springs exist (ooc: this can even be just a single one), whose water has medicinal properties, specifically affecting the intestines and the gut, aiding with constipation and other infections. Acid sulfate springs, while also blue-green like bicarbonate ones, are often surrounded by fungi, and many travel to areas around these springs to collect them.
Finally to the south, are the main (ie biggest) springs in Sakuran, surrounded by the blue circle. Affected by the same lava flows that gave rise to the cinder cones, these are alkali chloride ones. They have pure blue colours, are mineral rich and have general healing properties. The two biggest hot springs rise from the caldera of the now extinct westernmost cinder cones, after underground water found its way through the empty, but hot, lava flow chambers. The water flow from these two source is great enough to have created a small river riding down the slope of Mt. Achuachu, with life thriving around it. It's no wonder the capital of Shikemura (not on map) was built near this area.
